What is Kd?
Also, in reply to earlier posts: it is sadly common in crystallizing large protein-DNA complexes to go through a couple dozen different duplexes and several dismally-diffracting crystal forms before finding a good one.
Phoebe
>From: CCP4 bulletin board <[log in to unmask]> (on behalf of umar farook <[log in to unmask]>)
>Subject: [ccp4bb] Protein-DNA complex crystallization
>To: [log in to unmask]
>
> Dear All,
> I have been trying to crystallize protein DNA
> complex, but all the time i end up with DNA
> crystals. Even i changed the length of DNA many
> times but still no complex, DNA only crystallizes!
> Does anybody has idea, why do DNA crystallize by
> itself ? My protein behaves very nicely, Dynamic
> Light Scattering always shows nice values implies
> homogenous but once i tried to ran acidic native
> page but it shows little bit aggregated. The protein
> is highly hydrophilic and soluble, and has only
> three cysteines, is it there any possibility of
> aggregation due to cysteine, when overexpressed in
> E.coli ? and one more thing i mixed protein and DNA
> together and ran agarose gel to see any gel shift,
> indeed there is a binding, but when i take the same
> thing to set drops, only DNA crystals. Kindly
> suggest me, what could be done.
> Thanks & Regards,
> Umar Farook.S
|